[FieldTrip] headshape realigment

Nathan Weisz nathanweisz at mac.com
Thu Nov 22 14:39:19 CET 2012


Dear Mikel,

see attached file.

basically this function segments the fiducial-based-coregistered MR and alters the transformation-matrix to best fit the headshape in a least-squares sense. in practice, if your first coregistration was not too terrible this works quite fine. you can remove some very outlying headshape points as well.

see some docs here:
https://wiki.cimec.unitn.it/tiki-index.php?page=MRICoreg

some steps are quite lengthy (segmentation) and coded in frankenstein-style (i.e. mostly by me). so if you have improvements on the code, we would be happy to get them as well.

ciao,
nathan




On 22.11.2012, at 14:21, Mikel Lizarazu wrote:

> Dear Fieldtrippers,
>  I am working with MEG data from Elekta and T1 images.
> I am realigning MEG data with T1 images using ft_volumerealign function selecting N,LPA,RPA points. However, I would like to know if there is a possibility to also include the headshape information (isotrak data) in the realignment to obtain a better final result.
> Many thanks for your answers,
> Patrick
> 
> -- 
> Mikel Lizarazu
> Predoctoral researcher
> www.bcbl.eu
> _______________________________________________
> fieldtrip mailing list
> fieldtrip at donders.ru.nl
> http://mailman.science.ru.nl/mailman/listinfo/fieldtrip
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